src/modules/extra/m_ssl_gnutls.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2009 InspIRCd Development Team
   6  * See: http://wiki.inspircd.org/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *          the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 #include "inspircd.h"
  15 #include <gnutls/gnutls.h>
  16 #include <gnutls/x509.h>
  17 #include "transport.h"
  18 #include "m_cap.h"
  19
  20 #ifdef WINDOWS
  21 #pragma comment(lib, "libgnutls-13.lib")
  22 #endif
  23
  24 /* $ModDesc: Provides SSL support for clients */
  25 /* $CompileFlags: pkgconfincludes("gnutls","/gnutls/gnutls.h","") */
  26 /* $LinkerFlags: rpath("pkg-config --libs gnutls") pkgconflibs("gnutls","/libgnutls.so","-lgnutls") */
  27 /* $ModDep: transport.h */
  28 /* $CopyInstall: conf/key.pem $(CONPATH) */
  29 /* $CopyInstall: conf/cert.pem $(CONPATH) */
  30
  31 enum issl_status { ISSL_NONE, ISSL_HANDSHAKING_READ, ISSL_HANDSHAKING_WRITE, ISSL_HANDSHAKEN, ISSL_CLOSING, ISSL_CLOSED };
  32
  33 static gnutls_x509_crt_t x509_cert;
  34 static gnutls_x509_privkey_t x509_key;
  35 static int cert_callback (gnutls_session_t session, const gnutls_datum_t * req_ca_rdn, int nreqs,
  36         const gnutls_pk_algorithm_t * sign_algos, int sign_algos_length, gnutls_retr_st * st) {
  37
  38         st->type = GNUTLS_CRT_X509;
  39         st->ncerts = 1;
  40         st->cert.x509 = &x509_cert;
  41         st->key.x509 = x509_key;
  42         st->deinit_all = 0;
  43
  44         return 0;
  45 }
  46
  47 /** Represents an SSL user's extra data
  48  */
  49 class issl_session : public classbase
  50 {
  51 public:
  52         issl_session()
  53         {
  54                 sess = NULL;
  55         }
  56
  57         gnutls_session_t sess;
  58         issl_status status;
  59 };
  60
  61 class CommandStartTLS : public Command
  62 {
  63  public:
  64         CommandStartTLS (Module* mod) : Command(mod, "STARTTLS")
  65         {
  66                 works_before_reg = true;
  67         }
  68
  69         CmdResult Handle (const std::vector<std::string> &parameters, User *user)
  70         {
  71                 /* changed from == REG_ALL to catch clients sending STARTTLS
  72                  * after NICK and USER but before OnUserConnect completes and
  73                  * give a proper error message (see bug #645) - dz
  74                  */
  75                 if (user->registered != REG_NONE)
  76                 {
  77                         user->WriteNumeric(691, "%s :STARTTLS is not permitted after client registration has started", user->nick.c_str());
  78                 }
  79                 else
  80                 {
  81                         if (!user->GetIOHook())
  82                         {
  83                                 user->WriteNumeric(670, "%s :STARTTLS successful, go ahead with TLS handshake", user->nick.c_str());
  84                                 user->AddIOHook(creator);
  85                                 creator->OnStreamSocketAccept(user, NULL, NULL);
  86                         }
  87                         else
  88                                 user->WriteNumeric(691, "%s :STARTTLS failure", user->nick.c_str());
  89                 }
  90
  91                 return CMD_FAILURE;
  92         }
  93 };
  94
  95 class ModuleSSLGnuTLS : public Module
  96 {
  97         std::set<ListenSocketBase*> listenports;
  98
  99         issl_session* sessions;
 100
 101         gnutls_certificate_credentials x509_cred;
 102         gnutls_dh_params dh_params;
 103
 104         std::string keyfile;
 105         std::string certfile;
 106         std::string cafile;
 107         std::string crlfile;
 108         std::string sslports;
 109         int dh_bits;
 110
 111         bool cred_alloc;
 112
 113         CommandStartTLS starttls;
 114
 115         GenericCap capHandler;
 116  public:
 117
 118         ModuleSSLGnuTLS(InspIRCd* Me)
 119                 : Module(Me), starttls(this), capHandler(this, "tls")
 120         {
 121                 ServerInstance->Modules->PublishInterface("BufferedSocketHook", this);
 122
 123                 sessions = new issl_session[ServerInstance->SE->GetMaxFds()];
 124
 125                 gnutls_global_init(); // This must be called once in the program
 126                 gnutls_x509_crt_init(&x509_cert);
 127                 gnutls_x509_privkey_init(&x509_key);
 128
 129                 cred_alloc = false;
 130                 // Needs the flag as it ignores a plain /rehash
 131                 OnModuleRehash(NULL,"ssl");
 132
 133                 // Void return, guess we assume success
 134                 gnutls_certificate_set_dh_params(x509_cred, dh_params);
 135                 Implementation eventlist[] = { I_On005Numeric, I_OnRequest, I_OnRehash, I_OnModuleRehash, I_OnPostConnect,
 136                         I_OnEvent, I_OnHookIO };
 137                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 138
 139                 ServerInstance->AddCommand(&starttls);
 140         }
 141
 142         void OnRehash(User* user)
 143         {
 144                 ConfigReader Conf(ServerInstance);
 145
 146                 listenports.clear();
 147                 sslports.clear();
 148
 149                 for (size_t i = 0; i < ServerInstance->ports.size(); i++)
 150                 {
 151                         ListenSocketBase* port = ServerInstance->ports[i];
 152                         std::string desc = port->GetDescription();
 153                         if (desc != "gnutls")
 154                                 continue;
 155
 156                         listenports.insert(port);
 157                         std::string portid = port->GetBindDesc();
 158
 159                         ServerInstance->Logs->Log("m_ssl_gnutls", DEFAULT, "m_ssl_gnutls.so: Enabling SSL for port %s", portid.c_str());
 160                         if (port->GetIP() != "127.0.0.1")
 161                                 sslports.append(portid).append(";");
 162                 }
 163
 164                 if (!sslports.empty())
 165                         sslports.erase(sslports.end() - 1);
 166         }
 167
 168         void OnModuleRehash(User* user, const std::string &param)
 169         {
 170                 if(param != "ssl")
 171                         return;
 172
 173                 OnRehash(user);
 174
 175                 ConfigReader Conf(ServerInstance);
 176
 177                 std::string confdir(ServerInstance->ConfigFileName);
 178                 // +1 so we the path ends with a /
 179                 confdir = confdir.substr(0, confdir.find_last_of('/') + 1);
 180
 181                 cafile = Conf.ReadValue("gnutls", "cafile", 0);
 182                 crlfile = Conf.ReadValue("gnutls", "crlfile", 0);
 183                 certfile = Conf.ReadValue("gnutls", "certfile", 0);
 184                 keyfile = Conf.ReadValue("gnutls", "keyfile", 0);
 185                 dh_bits = Conf.ReadInteger("gnutls", "dhbits", 0, false);
 186
 187                 // Set all the default values needed.
 188                 if (cafile.empty())
 189                         cafile = "ca.pem";
 190
 191                 if (crlfile.empty())
 192                         crlfile = "crl.pem";
 193
 194                 if (certfile.empty())
 195                         certfile = "cert.pem";
 196
 197                 if (keyfile.empty())
 198                         keyfile = "key.pem";
 199
 200                 if((dh_bits != 768) && (dh_bits != 1024) && (dh_bits != 2048) && (dh_bits != 3072) && (dh_bits != 4096))
 201                         dh_bits = 1024;
 202
 203                 // Prepend relative paths with the path to the config directory.
 204                 if ((cafile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(cafile)))
 205                         cafile = confdir + cafile;
 206
 207                 if ((crlfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(crlfile)))
 208                         crlfile = confdir + crlfile;
 209
 210                 if ((certfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(certfile)))
 211                         certfile = confdir + certfile;
 212
 213                 if ((keyfile[0] != '/') && (!ServerInstance->Config->StartsWithWindowsDriveLetter(keyfile)))
 214                         keyfile = confdir + keyfile;
 215
 216                 int ret;
 217
 218                 if (cred_alloc)
 219                 {
 220                         // Deallocate the old credentials
 221                         gnutls_dh_params_deinit(dh_params);
 222                         gnutls_certificate_free_credentials(x509_cred);
 223                 }
 224                 else
 225                         cred_alloc = true;
 226
 227                 if((ret = gnutls_certificate_allocate_credentials(&x509_cred)) < 0)
 228                         ServerInstance->Logs->Log("m_ssl_gnutls",DEBUG, "m_ssl_gnutls.so: Failed to allocate certificate credentials: %s", gnutls_strerror(ret));
 229
 230                 if((ret =gnutls_certificate_set_x509_trust_file(x509_cred, cafile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 231                         ServerInstance->Logs->Log("m_ssl_gnutls",DEBUG, "m_ssl_gnutls.so: Failed to set X.509 trust file '%s': %s", cafile.c_str(), gnutls_strerror(ret));
 232
 233                 if((ret = gnutls_certificate_set_x509_crl_file (x509_cred, crlfile.c_str(), GNUTLS_X509_FMT_PEM)) < 0)
 234                         ServerInstance->Logs->Log("m_ssl_gnutls",DEBUG, "m_ssl_gnutls.so: Failed to set X.509 CRL file '%s': %s", crlfile.c_str(), gnutls_strerror(ret));
 235
 236                 FileReader reader(ServerInstance);
 237
 238                 reader.LoadFile(certfile);
 239                 std::string cert_string = reader.Contents();
 240                 gnutls_datum_t cert_datum = { (unsigned char*)cert_string.data(), cert_string.length() };
 241
 242                 reader.LoadFile(keyfile);
 243                 std::string key_string = reader.Contents();
 244                 gnutls_datum_t key_datum = { (unsigned char*)key_string.data(), key_string.length() };
 245
 246                 // If this fails, no SSL port will work. At all. So, do the smart thing - throw a ModuleException
 247                 if((ret = gnutls_x509_crt_import(x509_cert, &cert_datum, GNUTLS_X509_FMT_PEM)) < 0)
 248                         throw ModuleException("Unable to load GnuTLS server certificate (" + certfile + "): " + std::string(gnutls_strerror(ret)));
 249
 250                 if((ret = gnutls_x509_privkey_import(x509_key, &key_datum, GNUTLS_X509_FMT_PEM)) < 0)
 251                         throw ModuleException("Unable to load GnuTLS server private key (" + keyfile + "): " + std::string(gnutls_strerror(ret)));
 252
 253                 if((ret = gnutls_certificate_set_x509_key(x509_cred, &x509_cert, 1, x509_key)) < 0)
 254                         throw ModuleException("Unable to set GnuTLS cert/key pair: " + std::string(gnutls_strerror(ret)));
 255
 256                 gnutls_certificate_client_set_retrieve_function (x509_cred, cert_callback);
 257
 258                 if((ret = gnutls_dh_params_init(&dh_params)) < 0)
 259                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to initialise DH parameters: %s", gnutls_strerror(ret));
 260
 261                 // This may be on a large (once a day or week) timer eventually.
 262                 GenerateDHParams();
 263         }
 264
 265         void GenerateDHParams()
 266         {
 267                 // Generate Diffie Hellman parameters - for use with DHE
 268                 // kx algorithms. These should be discarded and regenerated
 269                 // once a day, once a week or once a month. Depending on the
 270                 // security requirements.
 271
 272                 int ret;
 273
 274                 if((ret = gnutls_dh_params_generate2(dh_params, dh_bits)) < 0)
 275                         ServerInstance->Logs->Log("m_ssl_gnutls",DEFAULT, "m_ssl_gnutls.so: Failed to generate DH parameters (%d bits): %s", dh_bits, gnutls_strerror(ret));
 276         }
 277
 278         ~ModuleSSLGnuTLS()
 279         {
 280                 gnutls_x509_crt_deinit(x509_cert);
 281                 gnutls_x509_privkey_deinit(x509_key);
 282                 gnutls_dh_params_deinit(dh_params);
 283                 gnutls_certificate_free_credentials(x509_cred);
 284                 gnutls_global_deinit();
 285                 ServerInstance->Modules->UnpublishInterface("BufferedSocketHook", this);
 286                 delete[] sessions;
 287         }
 288
 289         void OnCleanup(int target_type, void* item)
 290         {
 291                 if(target_type == TYPE_USER)
 292                 {
 293                         User* user = static_cast<User*>(item);
 294
 295                         if (user->GetIOHook() == this)
 296                         {
 297                                 // User is using SSL, they're a local user, and they're using one of *our* SSL ports.
 298                                 // Potentially there could be multiple SSL modules loaded at once on different ports.
 299                                 ServerInstance->Users->QuitUser(user, "SSL module unloading");
 300                                 user->DelIOHook();
 301                         }
 302                 }
 303         }
 304
 305         Version GetVersion()
 306         {
 307                 return Version("$Id$", VF_VENDOR, API_VERSION);
 308         }
 309
 310
 311         void On005Numeric(std::string &output)
 312         {
 313                 if (!sslports.empty())
 314                         output.append(" SSL=" + sslports);
 315                 output.append(" STARTTLS");
 316         }
 317
 318         void OnHookIO(StreamSocket* user, ListenSocketBase* lsb)
 319         {
 320                 if (!user->GetIOHook() && listenports.find(lsb) != listenports.end())
 321                 {
 322                         /* Hook the user with our module */
 323                         user->AddIOHook(this);
 324                 }
 325         }
 326
 327         const char* OnRequest(Request* request)
 328         {
 329                 ISHRequest* ISR = static_cast<ISHRequest*>(request);
 330                 if (strcmp("IS_NAME", request->GetId()) == 0)
 331                 {
 332                         return "gnutls";
 333                 }
 334                 else if (strcmp("IS_HOOK", request->GetId()) == 0)
 335                 {
 336                         ISR->Sock->AddIOHook(this);
 337                         return "OK";
 338                 }
 339                 else if (strcmp("IS_UNHOOK", request->GetId()) == 0)
 340                 {
 341                         ISR->Sock->DelIOHook();
 342                         return "OK";
 343                 }
 344                 else if (strcmp("IS_HSDONE", request->GetId()) == 0)
 345                 {
 346                         if (ISR->Sock->GetFd() < 0)
 347                                 return "OK";
 348
 349                         issl_session* session = &sessions[ISR->Sock->GetFd()];
 350                         return (session->status == ISSL_HANDSHAKING_READ || session->status == ISSL_HANDSHAKING_WRITE) ? NULL : "OK";
 351                 }
 352                 else if (strcmp("IS_ATTACH", request->GetId()) == 0)
 353                 {
 354                         if (ISR->Sock->GetFd() > -1)
 355                         {
 356                                 issl_session* session = &sessions[ISR->Sock->GetFd()];
 357                                 if (session->sess)
 358                                 {
 359                                         if (static_cast<Extensible*>(ServerInstance->SE->GetRef(ISR->Sock->GetFd())) == static_cast<Extensible*>(ISR->Sock))
 360                                         {
 361                                                 return "OK";
 362                                         }
 363                                 }
 364                         }
 365                 }
 366                 else if (strcmp("GET_CERT", request->GetId()) == 0)
 367                 {
 368                         Module* sslinfo = ServerInstance->Modules->Find("m_sslinfo.so");
 369                         if (sslinfo)
 370                                 return sslinfo->OnRequest(request);
 371                 }
 372                 return NULL;
 373         }
 374
 375
 376         void OnStreamSocketAccept(StreamSocket* user, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server)
 377         {
 378                 int fd = user->GetFd();
 379                 issl_session* session = &sessions[fd];
 380
 381                 /* For STARTTLS: Don't try and init a session on a socket that already has a session */
 382                 if (session->sess)
 383                         return;
 384
 385                 gnutls_init(&session->sess, GNUTLS_SERVER);
 386
 387                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 388                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 389                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 390
 391                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(fd)); // Give gnutls the fd for the socket.
 392
 393                 gnutls_certificate_server_set_request(session->sess, GNUTLS_CERT_REQUEST); // Request client certificate if any.
 394
 395                 Handshake(session, user);
 396         }
 397
 398         void OnStreamSocketConnect(StreamSocket* user)
 399         {
 400                 issl_session* session = &sessions[user->GetFd()];
 401
 402                 gnutls_init(&session->sess, GNUTLS_CLIENT);
 403
 404                 gnutls_set_default_priority(session->sess); // Avoid calling all the priority functions, defaults are adequate.
 405                 gnutls_credentials_set(session->sess, GNUTLS_CRD_CERTIFICATE, x509_cred);
 406                 gnutls_dh_set_prime_bits(session->sess, dh_bits);
 407                 gnutls_transport_set_ptr(session->sess, reinterpret_cast<gnutls_transport_ptr_t>(user->GetFd()));
 408
 409                 Handshake(session, user);
 410         }
 411
 412         void OnStreamSocketClose(StreamSocket* user)
 413         {
 414                 CloseSession(&sessions[user->GetFd()]);
 415         }
 416
 417         int OnStreamSocketRead(StreamSocket* user, std::string& recvq)
 418         {
 419                 issl_session* session = &sessions[user->GetFd()];
 420
 421                 if (!session->sess)
 422                 {
 423                         CloseSession(session);
 424                         user->SetError("No SSL session");
 425                         return -1;
 426                 }
 427
 428                 if (session->status == ISSL_HANDSHAKING_READ)
 429                 {
 430                         // The handshake isn't finished, try to finish it.
 431
 432                         if(!Handshake(session, user))
 433                         {
 434                                 if (session->status != ISSL_CLOSING)
 435                                         return 0;
 436                                 user->SetError("Handshake Failed");
 437                                 return -1;
 438                         }
 439                 }
 440                 else if (session->status == ISSL_HANDSHAKING_WRITE)
 441                 {
 442                         MakePollWrite(user);
 443                         return 0;
 444                 }
 445
 446                 // If we resumed the handshake then session->status will be ISSL_HANDSHAKEN.
 447
 448                 if (session->status == ISSL_HANDSHAKEN)
 449                 {
 450                         char* buffer = ServerInstance->GetReadBuffer();
 451                         size_t bufsiz = ServerInstance->Config->NetBufferSize;
 452                         size_t len = 0;
 453                         while (len < bufsiz)
 454                         {
 455                                 int ret = gnutls_record_recv(session->sess, buffer + len, bufsiz - len);
 456                                 if (ret > 0)
 457                                 {
 458                                         len += ret;
 459                                 }
 460                                 else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 461                                 {
 462                                         break;
 463                                 }
 464                                 else if (ret == 0)
 465                                 {
 466                                         user->SetError("SSL Connection closed");
 467                                         CloseSession(session);
 468                                         return -1;
 469                                 }
 470                                 else
 471                                 {
 472                                         user->SetError(gnutls_strerror(ret));
 473                                         CloseSession(session);
 474                                         return -1;
 475                                 }
 476                         }
 477                         if (len)
 478                         {
 479                                 recvq.append(buffer, len);
 480                                 return 1;
 481                         }
 482                 }
 483                 else if (session->status == ISSL_CLOSING)
 484                         return -1;
 485
 486                 return 0;
 487         }
 488
 489         int OnStreamSocketWrite(StreamSocket* user, std::string& sendq)
 490         {
 491                 issl_session* session = &sessions[user->GetFd()];
 492
 493                 if (!session->sess)
 494                 {
 495                         CloseSession(session);
 496                         user->SetError("No SSL session");
 497                         return -1;
 498                 }
 499
 500                 if (session->status == ISSL_HANDSHAKING_WRITE || session->status == ISSL_HANDSHAKING_READ)
 501                 {
 502                         // The handshake isn't finished, try to finish it.
 503                         Handshake(session, user);
 504                         if (session->status != ISSL_CLOSING)
 505                                 return 0;
 506                         user->SetError("Handshake Failed");
 507                         return -1;
 508                 }
 509
 510                 int ret = 0;
 511
 512                 if (session->status == ISSL_HANDSHAKEN)
 513                 {
 514                         ret = gnutls_record_send(session->sess, sendq.data(), sendq.length());
 515
 516                         if (ret == (int)sendq.length())
 517                         {
 518                                 return 1;
 519                         }
 520                         else if (ret > 0)
 521                         {
 522                                 sendq = sendq.substr(ret);
 523                                 MakePollWrite(user);
 524                                 return 0;
 525                         }
 526                         else if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 527                         {
 528                                 MakePollWrite(user);
 529                                 return 0;
 530                         }
 531                         else if (ret == 0)
 532                         {
 533                                 CloseSession(session);
 534                                 user->SetError("SSL Connection closed");
 535                                 return -1;
 536                         }
 537                         else // (ret < 0)
 538                         {
 539                                 user->SetError(gnutls_strerror(ret));
 540                                 CloseSession(session);
 541                                 return -1;
 542                         }
 543                 }
 544
 545                 return 0;
 546         }
 547
 548         bool Handshake(issl_session* session, EventHandler* user)
 549         {
 550                 int ret = gnutls_handshake(session->sess);
 551
 552                 if (ret < 0)
 553                 {
 554                         if(ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
 555                         {
 556                                 // Handshake needs resuming later, read() or write() would have blocked.
 557
 558                                 if(gnutls_record_get_direction(session->sess) == 0)
 559                                 {
 560                                         // gnutls_handshake() wants to read() again.
 561                                         session->status = ISSL_HANDSHAKING_READ;
 562                                 }
 563                                 else
 564                                 {
 565                                         // gnutls_handshake() wants to write() again.
 566                                         session->status = ISSL_HANDSHAKING_WRITE;
 567                                         MakePollWrite(user);
 568                                 }
 569                         }
 570                         else
 571                         {
 572                                 CloseSession(session);
 573                                 session->status = ISSL_CLOSING;
 574                         }
 575
 576                         return false;
 577                 }
 578                 else
 579                 {
 580                         // Change the seesion state
 581                         session->status = ISSL_HANDSHAKEN;
 582
 583                         VerifyCertificate(session,user);
 584
 585                         // Finish writing, if any left
 586                         MakePollWrite(user);
 587
 588                         return true;
 589                 }
 590         }
 591
 592         void OnPostConnect(User* user)
 593         {
 594                 // This occurs AFTER OnUserConnect so we can be sure the
 595                 // protocol module has propagated the NICK message.
 596                 if (user->GetIOHook() == this && (IS_LOCAL(user)))
 597                 {
 598                         if (sessions[user->GetFd()].sess)
 599                         {
 600                                 std::string cipher = gnutls_kx_get_name(gnutls_kx_get(sessions[user->GetFd()].sess));
 601                                 cipher.append("-").append(gnutls_cipher_get_name(gnutls_cipher_get(sessions[user->GetFd()].sess))).append("-");
 602                                 cipher.append(gnutls_mac_get_name(gnutls_mac_get(sessions[user->GetFd()].sess)));
 603                                 user->WriteServ("NOTICE %s :*** You are connected using SSL cipher \"%s\"", user->nick.c_str(), cipher.c_str());
 604                         }
 605                 }
 606         }
 607
 608         void MakePollWrite(EventHandler* eh)
 609         {
 610                 ServerInstance->SE->WantWrite(eh);
 611         }
 612
 613         void CloseSession(issl_session* session)
 614         {
 615                 if(session->sess)
 616                 {
 617                         gnutls_bye(session->sess, GNUTLS_SHUT_WR);
 618                         gnutls_deinit(session->sess);
 619                 }
 620
 621                 session->sess = NULL;
 622                 session->status = ISSL_NONE;
 623         }
 624
 625         void VerifyCertificate(issl_session* session, Extensible* user)
 626         {
 627                 if (!session->sess || !user)
 628                         return;
 629
 630                 Module* sslinfo = ServerInstance->Modules->Find("m_sslinfo.so");
 631                 if (!sslinfo)
 632                         return;
 633
 634                 unsigned int status;
 635                 const gnutls_datum_t* cert_list;
 636                 int ret;
 637                 unsigned int cert_list_size;
 638                 gnutls_x509_crt_t cert;
 639                 char name[MAXBUF];
 640                 unsigned char digest[MAXBUF];
 641                 size_t digest_size = sizeof(digest);
 642                 size_t name_size = sizeof(name);
 643                 ssl_cert* certinfo = new ssl_cert;
 644
 645                 /* This verification function uses the trusted CAs in the credentials
 646                  * structure. So you must have installed one or more CA certificates.
 647                  */
 648                 ret = gnutls_certificate_verify_peers2(session->sess, &status);
 649
 650                 if (ret < 0)
 651                 {
 652                         certinfo->error = std::string(gnutls_strerror(ret));
 653                         goto info_done;
 654                 }
 655
 656                 certinfo->invalid = (status & GNUTLS_CERT_INVALID);
 657                 certinfo->unknownsigner = (status & GNUTLS_CERT_SIGNER_NOT_FOUND);
 658                 certinfo->revoked = (status & GNUTLS_CERT_REVOKED);
 659                 certinfo->trusted = !(status & GNUTLS_CERT_SIGNER_NOT_CA);
 660
 661                 /* Up to here the process is the same for X.509 certificates and
 662                  * OpenPGP keys. From now on X.509 certificates are assumed. This can
 663                  * be easily extended to work with openpgp keys as well.
 664                  */
 665                 if (gnutls_certificate_type_get(session->sess) != GNUTLS_CRT_X509)
 666                 {
 667                         certinfo->error = "No X509 keys sent";
 668                         goto info_done;
 669                 }
 670
 671                 ret = gnutls_x509_crt_init(&cert);
 672                 if (ret < 0)
 673                 {
 674                         certinfo->error = gnutls_strerror(ret);
 675                         goto info_done;
 676                 }
 677
 678                 cert_list_size = 0;
 679                 cert_list = gnutls_certificate_get_peers(session->sess, &cert_list_size);
 680                 if (cert_list == NULL)
 681                 {
 682                         certinfo->error = "No certificate was found";
 683                         goto info_done_dealloc;
 684                 }
 685
 686                 /* This is not a real world example, since we only check the first
 687                  * certificate in the given chain.
 688                  */
 689
 690                 ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
 691                 if (ret < 0)
 692                 {
 693                         certinfo->error = gnutls_strerror(ret);
 694                         goto info_done_dealloc;
 695                 }
 696
 697                 gnutls_x509_crt_get_dn(cert, name, &name_size);
 698                 certinfo->dn = name;
 699
 700                 gnutls_x509_crt_get_issuer_dn(cert, name, &name_size);
 701                 certinfo->issuer = name;
 702
 703                 if ((ret = gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_MD5, digest, &digest_size)) < 0)
 704                 {
 705                         certinfo->error = gnutls_strerror(ret);
 706                 }
 707                 else
 708                 {
 709                         certinfo->fingerprint = irc::hex(digest, digest_size);
 710                 }
 711
 712                 /* Beware here we do not check for errors.
 713                  */
 714                 if ((gnutls_x509_crt_get_expiration_time(cert) < ServerInstance->Time()) || (gnutls_x509_crt_get_activation_time(cert) > ServerInstance->Time()))
 715                 {
 716                         certinfo->error = "Not activated, or expired certificate";
 717                 }
 718
 719 info_done_dealloc:
 720                 gnutls_x509_crt_deinit(cert);
 721 info_done:
 722                 BufferedSocketFingerprintSubmission(user, this, sslinfo, certinfo).Send();
 723         }
 724
 725         void OnEvent(Event* ev)
 726         {
 727                 capHandler.HandleEvent(ev);
 728         }
 729 };
 730
 731 MODULE_INIT(ModuleSSLGnuTLS)